general protection fault, probably for non-canonical address 0xdffffc000000003e: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x00000000000001f0-0x00000000000001f7] CPU: 0 PID: 32373 Comm: syz-executor.2 Not tainted 5.12.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__fib6_drop_pcpu_from.part.0+0xfc/0x280 net/ipv6/ip6_fib.c:977 Code: 48 c1 e8 03 80 3c 18 00 0f 85 36 01 00 00 4d 8b 3f 4d 85 ff 0f 84 5a ff ff ff e8 df 77 bc f9 49 8d 7f 70 48 89 f8 48 c1 e8 03 <80> 3c 18 00 0f 85 5d 01 00 00 49 8b 47 70 48 3b 44 24 08 0f 85 31 RSP: 0018:ffffc900091372b8 EFLAGS: 00010203 RAX: 000000000000003e RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffff88805f36d4c0 RSI: ffffffff87b77991 RDI: 00000000000001f6 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8fa99947 R10: ffffffff87b7791d R11: 0000000000000000 R12: 0000000000000007 R13: ffff88806091a2a0 R14: fffffbfff1b8a4ac R15: 0000000000000186 FS: 00000000020fe400(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000056c000 CR3: 00000000126e2000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __fib6_drop_pcpu_from net/ipv6/ip6_fib.c:959 [inline] fib6_drop_pcpu_from net/ipv6/ip6_fib.c:1020 [inline] fib6_purge_rt+0x6a3/0x810 net/ipv6/ip6_fib.c:1031 fib6_del_route net/ipv6/ip6_fib.c:1982 [inline] fib6_del+0xa92/0x15a0 net/ipv6/ip6_fib.c:2027 fib6_clean_node+0x398/0x5c0 net/ipv6/ip6_fib.c:2189 fib6_walk_continue+0x4aa/0x8e0 net/ipv6/ip6_fib.c:2111 fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2159 fib6_clean_tree+0xdb/0x120 net/ipv6/ip6_fib.c:2239 __fib6_clean_all+0x120/0x290 net/ipv6/ip6_fib.c:2255 rt6_sync_down_dev net/ipv6/route.c:4768 [inline] rt6_disable_ip+0x77f/0x890 net/ipv6/route.c:4773 addrconf_ifdown.isra.0+0xf6/0x15b0 net/ipv6/addrconf.c:3706 addrconf_notify+0x55c/0x23e0 net/ipv6/addrconf.c:3631 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2075 call_netdevice_notifiers_extack net/core/dev.c:2087 [inline] call_netdevice_notifiers net/core/dev.c:2101 [inline] dev_close_many+0x2ff/0x620 net/core/dev.c:1676 unregister_netdevice_many+0x3fd/0x1760 net/core/dev.c:10913 unregister_netdevice_queue+0x2dd/0x3c0 net/core/dev.c:10870 unregister_netdevice include/linux/netdevice.h:2884 [inline] __tun_detach+0x105a/0x13d0 drivers/net/tun.c:670 tun_detach drivers/net/tun.c:687 [inline] tun_chr_close+0xd9/0x180 drivers/net/tun.c:3395 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:140 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x249/0x250 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x41940b Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007ffe0f6e5ed0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000006 RCX: 000000000041940b RDX: 00000000d96641f2 RSI: 000000000c574e12 RDI: 0000000000000005 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000001b32027e44 R10: 000000000002892c R11: 0000000000000293 R12: 000000000056c9e0 R13: 000000000056c9e0 R14: 000000000056bf60 R15: 00000000000cc979 Modules linked in: ---[ end trace 29019239076c2da2 ]--- RIP: 0010:__fib6_drop_pcpu_from.part.0+0xfc/0x280 net/ipv6/ip6_fib.c:977 Code: 48 c1 e8 03 80 3c 18 00 0f 85 36 01 00 00 4d 8b 3f 4d 85 ff 0f 84 5a ff ff ff e8 df 77 bc f9 49 8d 7f 70 48 89 f8 48 c1 e8 03 <80> 3c 18 00 0f 85 5d 01 00 00 49 8b 47 70 48 3b 44 24 08 0f 85 31 RSP: 0018:ffffc900091372b8 EFLAGS: 00010203 RAX: 000000000000003e RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffff88805f36d4c0 RSI: ffffffff87b77991 RDI: 00000000000001f6 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8fa99947 R10: ffffffff87b7791d R11: 0000000000000000 R12: 0000000000000007 R13: ffff88806091a2a0 R14: fffffbfff1b8a4ac R15: 0000000000000186 FS: 00000000020fe400(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000056c000 CR3: 00000000126e2000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600